1. Field of the Invention
The present invention relates to a backlight device that illuminates a transmissive liquid crystal panel and a liquid crystal display apparatus including the backlight device.
2. Description of the Related Art
A liquid crystal display apparatus has liquid crystal filled between two transparent substrates. The application of voltage thereto changes the direction of liquid crystal molecules and thus changes the optical transmittance, whereby the liquid crystal display apparatus can optically display a predetermined picture. Since liquid crystal itself does not contain a light emitter, some liquid crystal display apparatus may include a backlight device that irradiates radiates illumination light by using a light emitting diode (or LED) as a light source to the back side of a liquid crystal panel, for example (refer to JP-A-2006-058486 (Patent Document 1)). The backlight device connects to a plurality of light source substrates having a plurality of LEDs through wiring members such as harnesses and is attached to a bottom chassis, for example, with a double-faced adhesive tape, for example.
However, in the backlight device, if the light source substrates are warped, if the light source substrates and the bottom chassis contain different materials with different thermal expansion coefficients and therefore with different degrees of thermal expansion or if the bottom chassis has projections and depressions, for example, it is difficult to keep the intimate contact between the light source substrates and the bottom chassis during operations, which lifts the light source substrates off the bottom chassis and produces a gap between the light source substrates and the bottom chassis.